Security systems are widely used for monitoring fixed-sites such as, for example, buildings, commercial establishments or outdoor areas. These systems are configured in different ways, dependent upon the intended application, to fulfill the need for providing alarm indications. For example, one alarm indication may be provided as an audio signal emitted by a siren at the site. The alarm indication may be responsive to a motion detector, a smoke detector or other similar such detectors which are well known in the art. Another alarm indication may be provided to a central monitoring location via standard or dedicated telephone lines. From the central monitoring location, the proper authorities can be notified to respond to an immediate security threat at a particular site. This latter indication may be used in combination with the former, if so desired.
Some past fixed-site systems, as described above, also employ one or more video cameras to send an analog video signal to the monitoring station. In this way, personnel at the remote monitoring location can view the post-alarm state of the site whereby to determine if a response is warranted. Hence, response to false alarms by the authorities can be minimized. While these prior art fixed-site monitoring systems are generally effective, it should be appreciated that the adaptability of these systems for use in monitoring mobile, ground-based platforms is limited, as will be described below.
Unlike past fixed-site monitoring security systems, systems for use in mobile, ground-based platform monitoring applications have relied to a large extent on alarm signals emitted directly into the ambient environment of the platform in the hope that someone may respond or that the alarm signal itself will provide a deterrence. For example, automobile alarm systems, in most cases, provide an audio signal from a siren which may be accompanied by other signals such as, for example, flashing headlights. Unfortunately, response to these signals is far from assured. It should also be appreciated that mobile, ground-based platforms operate under a multitude of different conditions in a constantly changing ambient environment and that, in some cases, the emission of an audio alarm signal into the ambient environment of the platform may actually be inappropriate or inadequate. Moreover, the operational environment of the platform may dictate the need for forms of monitoring other than just system response to alarm events.
As an example, a public transportation bus is subject to emergency situations including terrorism, hijacking and accidents. In the aforementioned and other situations, the particular capability of fixed-site monitoring, in which a remote monitoring station is immediately notified of a problem, is most appropriate. Unfortunately, this capability is not provided in most mobile, ground-based systems of the past. Unlike fixed-site systems, a security system on a mobile platform, such as the bus of the present example, is not able to rely on fixed telephone lines for the communication of an alarm indication or any form of post-alarm image to a monitoring location.
Moreover, involvement of the bus in an accident with a pedestrian, another vehicle or with a stationary object is of intense concern for any number of reasons to public safety officials, the transportation utility which operates the bus and any insurance companies representing the respective entities. Public safety officials are interested in reducing emergency personnel response time and in arriving at the scene of an accident in possession of tools which may be needed for the particular situation. Further, the transportation utility operating the bus would like to know what caused the accident and who was at fault for use in formulating policies which will prevent the future occurrence of a similar accident. Insurance companies are, of course, interested in information establishing responsibility for the accident. Additionally, the utility's insurance company and the utility itself are interested in historical information determinate of who actually was on the bus and in what specific way they were injured. Such information is useful for purposes of reducing liability by limiting fraudulent claims. While prior art systems configured for monitoring mobile, ground-based platforms have attempted to address some of these needs, as described above, there has not yet been a sweeping approach which adequately resolves the various concerns. It should also be appreciated that only a few aspects of monitoring a particular type of mobile, ground-based platform have been described for exemplary purposes.
One proposed prior art system utilizes a video tape recording system on a school bus in an attempt to improve the behavior of the student passengers. The system provides a camera positioned above the driver for providing an analog video signal to a video tape recorder. A video history of the events occurring within the passenger compartment of the school bus is recorded on the tape. Such a system, within the context of the example of the public transportation bus above, may help to deter vandalism and, obviously, would provide a record of who was on the bus. However, the system is subject to the limitations imposed by an analog video tape system. For example, storage on a video tape is limited. The tape must, therefore, be changed frequently. Additionally, video tape does not provide for random access to a specific image contained thereon. Locating a particular recorded event requires an arduous review of the contents of the tape using the valuable time of security personnel. Aside from the limitations imposed just by the video tape itself, the system makes no provision for alarm indications which address the other situations described above.